Flying mosquitoes and cataracts are both common diseases in ophthalmology, but there is a big difference between the two: 1. Cataract patients are mainly examined by slit lamp microscopy and found to have cloudy lens. 3, the danger of the two is different, mosquito flying disease usually has mild symptoms and does not lead to vision loss and other eye diseases, cataract will gradually cause serious vision loss, and may lead to secondary glaucoma, uveitis and other complications. 4, the treatment is different, mosquito flying disease can be treated by oral Lecithin complex iodine treatment, cataracts need to be treated through surgery.